Norepinephrine, also called noradrenaline, or 4,5-β-trihydroxy phenethylamine is a catecholamine with multiple roles including those as a hormone and a neurotransmitter. It is the hormone and neurotransmitter most responsible for vigilant concentration in contrast to its most chemically similar hormone, dopamine, which is most responsible for cognitive alertness.
Medically it is used in those with severe hypotension. It does this by increasing vascular tone through α-adrenergic receptor activation.
Areas of the body that produce or are affected by norepinephrine are described as noradrenergic. The terms noradrenaline and norepinephrine are interchangeable, with noradrenaline being the common name in most parts of the world. However the U.S. National Library of Medicine has promoted norepinephrine as the favored name.
One of the most important functions of norepinephrine is its role as the neurotransmitter released from the sympathetic neurons to affect the heart. An increase in norepinephrine from the sympathetic nervous system increases the rate of contractions in the heart.
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Norepinephrine, also called noradrenaline, or 4,5-β-trihydroxy phenethylamine is a catecholamine...
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